Mid Term Review
In a parallel circuit, the current flow through the inductor will be _____.
90° out of phase with the voltage
In a parallel circuit, the voltage across the resistor and the voltage across the inductor are _____.
In Phase
When a capacitor has a potential difference between the plates, it is said to be _____. One plate has an excess of free electrons, and the other plate has a lack of them.
Charged
T or F Conductor resistance is directly proportional to the conductor's length and cross-sectional area.
False
T or F Eddy currents are small independent currents induced within the conductor because of direct current.
False
T or F A half-wave rectifier can be used to convert ac voltage into dc voltage to continuously charge a capacitor.
False (Full Wave)
What standard prefix in engineering notation indicates multiplication by 1,000,000,000?
GIGA
The neutral conductor is also referred to as the _____ conductor.
Grounded
The total current-limiting effect is called _____.
impedance
A capacitor can be thought of as a device that resists changes in current. Because a capacitor introduces reactance to the circuit, it shifts the current waveform to _____.
lead the applied voltage by 90°
In a capacitor, the voltage difference between the plates controls the _____.
amount of dielectric stress
Because inductive reactance and capacitive reactance are _____ out of phase with each other, they subtract from each other in an AC circuit.
180
In a purely inductive circuit, the CEMF waveform is _____ out-of-phase with the applied voltage waveform.
180
The waveform of the CEMF is _____ out-of-phase with the applied voltage.
180
Two inductors are connected in parallel to a 120-V, 60-Hz supply. The values of the inductors are 0.15 H and 0.225 H. The total amperage is _____.
3.54 A
Approximately how many horsepower is an electrical device listed as 3,000 watts?
4
Variable capacitors normally have a dielectric of _____.
Air
The induced voltage in a conductor carrying alternating current opposes the change in current flowing through the conductor. The induced voltage that opposes the current flow is called "_____."
All of these
Self-induced voltage is 180° out-of-phase with the _____. When the applied voltage is at its maximum in one direction, the induced voltage is at its maximum in the opposite direction.
Applied Voltage
What law states that the force of electrostatic attraction or repulsion is directly proportional to the product of the two charges and inversely proportional to the square of the distance between them?
Coulombs Law
Polarized capacitors are also known as _____ capacitors.
Electrolytic
The movement of electrons caused by an external magnetic field is called "_____ current," and the associated potential that is established is called "_____ voltage."
Induced
If a RLC series circuit contains more inductive VARs than capacitive VARs, the circuit has a _____ power factor.
Lagging
If the voltage in a RLC series circuit is ahead of the current, the power factor is referred to as _____.
Lagging
If a RLC series circuit contains more capacitive VARs than inductive VARs, then the circuit has a _____ power factor.
Leading
If the current leads the voltage in a RLC series circuit, the power factor is referred to as _____.
Leading
If the voltage is behind the current in a RLC series circuit, the power factor is referred to as _____.
Leading
In a pure capacitive circuit, the current _____ the applied voltage by _____.
Leads 90
In a parallel circuit, the total resistance is _____ value resistor.
Less than lowest
In a RLC series circuit, the point at which XL and XC are equal is called _____.
Resonance
As the alternating current through a conductor increases, an expanding and collapsing electromagnetic field through the conductor induces a voltage within the conductor. This is known as "_____ voltage."
Self-Induced
What type of circuit generally occurs when the conductors leading from and back to the power source become connected?
Short
T or F Because an iron core provides an easy path for magnetic flux, windings with soft iron cores produce a greater self-inductance than windings with air cores.
True
T or F Capacitors are used to start single-phase ac motors and to prevent arcing across the contacts of electric switches.
True
T or F Even when power is removed from the circuit, capacitors can store large amounts of energy for a long period of time, and can discharge and arc if inadvertently shorted or grounded out.
True
T or F When electrons move, the magnetic fields of the individual electrons combine to produce an overall magnetic field. The greater the current flow, the greater the overall magnetic field around the conductor.
True
The amount of electrical power being used in a circuit is measured in ____.
Watts
The material between a capacitor's plates is rated by a value called the _____.
dialectic constant
